期刊論文
學年 | 96 |
---|---|
學期 | 2 |
出版(發表)日期 | 2008-02-01 |
作品名稱 | Localized Gaussian Type Orbital−Periodic Boundary Condition−Density Functional Theory Study of Infinite-Length Single-Walled Carbon Nanotubes with Various Tubular Diameters |
作品名稱(其他語言) | |
著者 | Wang, Houng-Wei; Wang, Bo-Cheng; Chen, Wen-Hao; Hayashi, Michitoshi |
單位 | 淡江大學化學學系 |
出版者 | Washington, DC: American Chemical Society |
著錄名稱、卷期、頁數 | Journal of Physical Chemistry A 112(8), pp.1783-1790 |
摘要 | The detailed geometrical structures of zigzag and armchair type single-walled carbon nanotubes (SWCNTs) with infinite tubular length were investigated using localized Gaussian type orbital−periodic boundary condition−density functional theory (LGTO−PBC−DFT) method. The structures of (n, 0) zigzag SWCNTs were optimized for n = 5−21, (n, n) armchair SWCNTs for n = 3−12. For comparison, the optimized geometry of a two-dimensional graphite sheet was also calculated. It was found that the optimized structures of the SWCNTs showed two C−C bond lengths that decrease with an increase in the tubular diameter. More specifically, the two bond lengths converged with those found in the two-dimensional graphite sheet. We also found a degeneracy in the highest occupied crystal orbitals if identical bond lengths were employed for the zigzag SWCNTs and the two-dimensional graphite sheet. This implies that the two different bond lengths found in the zigzag SWCNTs and the two-dimensional graphite sheet are probably due to the Jahn−Teller effect. The armchair SWCNTs show two slightly different bond lengths if the diameter is less than 12 Å; otherwise they are almost identical, approaching the longer bond length of the two-dimensional graphite sheet. This can be due to the fact that the armchair SWCNTs do not have degeneracy in occupied crystal orbitals for identical C−C bond lengths. The crossing point of the conducting and valence bands of each armchair SWCNT were also calculated and show a diameter dependence in which the deviation from 2π/3a decreases as diameter increases. |
關鍵字 | Bond length;Boundary conditions;Density functional theory;Geometry;Optimization;Crystal orbitais;Tubular diameters;Single-walled carbon nanotubes (SWCN) |
語言 | en |
ISSN | 1089-5639 |
期刊性質 | 國外 |
收錄於 | SCI |
產學合作 | |
通訊作者 | Wang, Bo-Cheng; Hayashi, Michitoshi |
審稿制度 | |
國別 | USA |
公開徵稿 | |
出版型式 | 紙本 |
相關連結 |
機構典藏連結 ( http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/61643 ) |